Wood-grinder



(No Model.)

0. CORNWBLL.

1 WOOD GRINDER. No. 469,812.

Patented-Mar; 1,1892.

WWW. Y

UNITED STATES PATENT OFFICE.

CLARK CORNWELL, OF YPSILANTI, MICHIGAN.

WOOD-GRINDER.

SPECIFICATION forming part of Letters Patent No. 469,812, dated March 1, 1892.

I Application filed April 20, 1891. fierial No. 389,710. (No model.)

To all whom it may concern:

Be it known that I, CLARK CoRNWELL,-a citizen of the United States, residing at Ypsilanti, in the ooun-tyof WVashtenaw and'State of Michigan, have invented certain new and useful Improvements in Wood-Grinders, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

My invention relates to that class of grinders for reducing blocks of wood to pulp or fiber, in which a revolving stone is used to do the grinding and in which a series of blockpressers are employed to hold the wood under pressure against the face of the stone; and it has for its object the employment of means for preventing the regrinding of the pulp.

The novelty of my invention will be hereinafter set forth, and specifically pointed out in the claims.

In the accompanying drawings, Figure 1 is a sectional side elevation of a grinder embodying my invention. Fig. 2 is a sectional diagram in plan of so much of the machine as is necessary in the illustration of my invention. Fig. 3 is a corresponding view representing a modification in the construction.

The same letters of referen oe are used to indicate identical parts in all the figures.

The machine in general may be of the usual or any suitable construction and in describing it it is only necessary to say that A is the vertically-set revolving stone, hung on its shaft B and surrounded by the casing G of the usual or any suitable construction. Within the casing are the radially-set and adjustable pockets Din this instance three in number for containing the blocks of wood to be ground.

E are the usual or any suitable cylinders, containing pistons for actuating the presserplatens F which hold the wood against the face of the stonewith constant pressure.

G are the pipes With suitable valves for conveying Water or steam to the cylinders .E to actuate the pistons Within the same, and H is the water-pipe with branches I and perforated cross-pieces J for supplying Water to the face of the stone. The wood is introduced into the pockets D through suitable doors in the side of the casing O. Heretofore in cylinders of this class the pulp or fiber ground from one pocket would be carried under the next pocket and be reground,and so on under all the succeeding pockets, thereby, in many instances, reducing the pulp to a degree of fineness very undesirable. It is the purpose of my invention to prevent this regrinding of the pulp or fiber and to insure a uniform degree of coarseness or fineness for the pulp or fiber from all of the pockets, and to that end I secure between the pockets and upon the face of the stone scraper-bars K, which, as shown in Figs. 1 and 2, may be V-shaped, with the apex toward the direction of revolution of the stone, so that the pulp or fiber coming from each pocket is swept obliquely or diagonally in each direction aside over the edge of the stone and is prevented from passing on under the next pocket, or, as shown in Fig. 3, said scrapers may be substantially straight bars set diagonally to the face of the stone. The pulp or fiber thus swept off is deposited in the usual pit under the stone. The scraper-bars should be made adj List-able, so as to accommodate them snugly to the face of the stone as the latter Wears down, and as one method of adjustment I have shown them supported by set-screws a bearing in lugs 1) upon the casing, and in Figs. 1 and 2 upon the rear sides of the pockets. The scraperbars should be of sufficient depth to prevent the water and pulp from flowing over their top.

Having thus fully described my invention, I claim-- 1. In a wood-grinder, the combination, with the revolving stone and radially-set woodcontaining pockets, of scraper-bars interposed between the pockets and set diagonally upon theface of the stone, lugs b, and set-screws a passing through said lugs and serving to effect adjustment of the scraper-bars, substantially as described.

2. In a wood-grinder, the combination, with the revolving stone and radially-set wood-containin g pockets, of the V-shaped scraper-bars K, set-screws a, and lugs 11, substantially as described.

CLARK CORNW'ELL.

\Vitnesses: W. D. GREENE,

D. B. GREENE. 

